It appears that there is a guy named Eliezer Yudkowsky who claims he knows The Meaning of Life (and no (hold your breath), it's not 42), or more specifically, what we all should do, what we get out of our beds in the morning for.
Megabytes of his writings can be found online, but in bare essence, the philosophy boils down to:

We, humans, don't know the meaning of life.

But the species on earth are evolving quickly, with us, humans, being the latest and greatest.

We humans can work towards creating a true Artificial Intelligence, one that is equal to us in brain-power.

Once such an AI exists, since its hardware follows Moore's law, it will double in power each 18 months. Since it's smarter than we are, it will impove itself, and hence double in power even faster, until it reaches a point of Singularity - an infinite intelligence.

This will eventually lead us to a new state of awareness, when we create a super-intelligent being beyond human (transhumanism) and upload our brains into it - becoming immortal.

Being infinitely smarter than we are, this "transhuman state" will have a better chance of figuring the meaning of life.

Therefore, we do have an Interim meaning of life - to create such an AI.

There already exists a Singularity Institute, and they are actively designing this AI, laying down tons of documents with ideas and very detailed architectures and timelines. Quite curious actually, it sounds like a thing worth spending time on.

My exposition is probably lacking, but his ideas are rather compelling. A quick googling on "yudkowsky" brings up tons of material - check it out.